1. Field of the Invention
The present invention relates to a cordless telephone apparatus and a cordless telephone system, which are capable of using a mobile information terminal as a handset of a cordless telephone also outside of a house.
2. Description of the Related Art
In recent years, as household landline telephones, cordless types that are capable of being placed in a living room, a kitchen, a bedroom, and the like and being used as handsets, have been in wide use. Because the mere addition of a dedicated handset occurs an incidental cost, a service function that enables a smartphone already in use to be used as a handset of the cordless telephone is needed.
As a method of partly realizing this service function, a technology for an apparatus that enables a client on a packet-switched network such as the Internet to receive an incoming call from a circuit-switched network is known as disclosed in Japanese Patent Unexamined Publication No. 11-355358.
However, the technology disclosed in Japanese Patent Unexamined Publication No. 11-355358 achieves a purpose of making a notification of the incoming call to all mobile information terminals that are registered with the apparatus, but consideration is not given to ease of use in a case where the mobile information terminal is also used as a handset of the cordless telephone outside of a house. For example, regardless of the mobile information terminal carried outside of the house being able to answer a call from outside of the house, because a base unit of the cordless telephone performs automatic answering earlier, the mobile information terminal cannot answer and so forth.